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Problem with TUniLoader
Posted: Thu 09 Sep 2010 06:47
by PixAndMore
Hello,
for multiple inserts I have used TUniLoader. The performance is very good and it works for me on Firebird, MySQL, Oracle (DirectPath = False) and PostgreSQL....
But when I use the same routines for MS SQL 2005 Server, it works, but all characters in the Table have 2 Bytes! I can't see what for bytes, I see only a square, but I think its a null byte because when I load the record the length is limited on the first character...
Using TUniSQL, TUniQuery and TUniScript is ok and works, but not TUniLoader
Any Ideas?
Posted: Thu 09 Sep 2010 12:26
by Dimon
UniDAC maps the VARCHAR fields of SQL Server to the ftString field type and NVARCHAR to ftWideString. If you use NVARCHAR fields you should set value on loading data as WideString.
Code: Select all
if Column.FieldType = ftWideString then
Value := WideString('ABCD');
Posted: Thu 09 Sep 2010 12:36
by PixAndMore
Hello,
Dimon wrote:UniDAC maps the VARCHAR fields of SQL Server to the ftString field type and NVARCHAR to ftWideString. If you use NVARCHAR fields you should set value on loading data as WideString.
Code: Select all
if Column.FieldType = ftWideString then
Value := WideString('ABCD');
no I'm using normal VARCHAR Fields. Like said it works with all other components:
Code: Select all
uniquery.sql.text = 'insert into table(str) values(:str)';
uniquery.parambyname('str').Value := 'Hallo';
uniquery.execSQL;
unisql.sql.text = 'insert into table(str) values(:str)';
unisql.parambyname('str').Value := 'Hallo';
unisql.execute;
uniscript.sql.text = 'insert into table(str) values(:str);';
uniscript.statements[0].parambyname('str').Value := 'Hallo';
uniscript.exec;
That all works for all database, including MS SQL 2005.
Only TUniLoader on MS SQL makes problems! It looks like an UTF-16 problem? I don't use unicode...
Posted: Thu 09 Sep 2010 12:51
by PixAndMore
An additional info:
Posted: Fri 10 Sep 2010 13:09
by AndreyZ
I could not reproduce the problem. Please try to compose a small sample to demonstrate the problem and send it to andreyz*devart*com.
Posted: Thu 16 Sep 2010 07:43
by AndreyZ
Was the problem solved? If not, please, contact me.
Posted: Thu 16 Sep 2010 07:50
by PixAndMore
No it was not, I had send an email with an example to you...
(13.09.2010 / 12:00h)
I had also get a reading confirmation from you!
Posted: Thu 16 Sep 2010 09:13
by AndreyZ
This problem appears because RAD Studio takes strings as the WideString type since 2009. To solve the problem you have to cast strings to AnsiString explicitly. Here is an example:
Code: Select all
UniLoader.PutColumnData('updated', 1, AnsiString('00000000000000'));
Posted: Thu 16 Sep 2010 11:19
by PixAndMore
Yes, this works for me, thank you...
But I think it is only a workaround, because:
I have a method "GetAsParamValue: Variant", this methods works for
TUniQuery.Params[0].Value := GetAsParamValue
TUniSQL.Params[0].Value := GetAsParamValue
TUniScript.Statements[0].Params[0].Value := GetAsParamValue
TUniLoader.PutColumnData('f', 1, GetAsParamValue)
for Firebird, MySQL, MS SQL, Oracle and PostgreSQL. Only TUniLoader does not work for MS-SQL!
And: If want to use unicode in future, i have to fix again!?
Posted: Thu 16 Sep 2010 13:09
by AndreyZ
You can solve this problem in two ways:
- change field type in database to nvarchar instead varchar (nvarchar type support work with Unicode);
- do column type check when setting the value of the field like that:
Code: Select all
if UniLoader.Columns[1].FieldType = ftString then
UniLoader.PutColumnData(1, 1, AnsiString(GetAsParamValue))
else
UniLoader.PutColumnData(1, 1, GetAsParamValue);